Kasicka V, Prusík Z, Brynda E, Stejskal J
Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague.
Electrophoresis. 1999 Sep;20(12):2484-92. doi: 10.1002/(SICI)1522-2683(19990801)20:12<2484::AID-ELPS2484>3.0.CO;2-Q.
A new way of regulation of electroosmotic flow (EOF) in capillary zone electrophoresis (CZE) by external electric field has been developed. A set of three high-voltage power supplies is used to form a radial electric field across the capillary wall. One power supply is applied in the usual way as a driving force of CZE and EOF to the ends of the inner capillary compartment dipped into the electrode vessels and filled with background electrolyte. Two power supplies are connected to the ends of the outer low-conductivity coating of the capillary which is formed by the dispersion of copolymer of aniline and p-phenylenediamine in polystyrene matrix. The difference between electric potentials on the outer capillary surface and inside the capillary determines the voltage of radial electric field across the capillary wall and affects the electrokinetic potential at the solid-liquid interface inside the capillary. The effect of magnitude and polarity of external radial electric field on the flow rate of EOF, on the migration times of charged analytes and on the separation efficiency and resolution of CZE separations of synthetic oligopeptides, diglycine, triglycine and octapeptide fragments of human insulin was evaluated. Through the EOF control by external electric field the dynamic effective length of the capillary was obtained and the speed of analysis and resolution of CZE separations of peptide analytes could be optimized.
已开发出一种通过外部电场调节毛细管区带电泳（CZE）中电渗流（EOF）的新方法。使用一组三个高压电源在毛细管壁上形成径向电场。一个电源以常规方式作为CZE和EOF的驱动力施加到浸入电极容器并填充有背景电解质的毛细管内部隔室的两端。两个电源连接到由聚苯胺和对苯二胺的共聚物在聚苯乙烯基质中的分散体形成的毛细管外部低电导率涂层的两端。毛细管外表面和毛细管内部的电势差决定了穿过毛细管壁的径向电场的电压，并影响毛细管内部固液界面处的动电电位。评估了外部径向电场的大小和极性对EOF流速、带电分析物迁移时间以及合成寡肽、二甘氨酸、三甘氨酸和人胰岛素八肽片段的CZE分离的分离效率和分辨率的影响。通过外部电场对EOF的控制，获得了毛细管的动态有效长度，并且可以优化肽分析物的CZE分离的分析速度和分辨率。
